Kansas City Auto Electric here, Great video. I use this tester all of the time. I love the idea that it is old school and does not cost close to 1k like some of those digital ones do. The only thing I would like to add is when checking your charging system when using this load tester DO NOT use the toggle switch on the bottom. If you do you will short out the charging system. It is read-only. I know it should be obvious but I have seen so many people that do it and wonder why their car no longer runs.

Before using the device, make sure it is reading zero, before connecting to battery. The device is fairly accurate, but only if it starts at zero. If it is not at zero, all of your measurements are worthless. Don't assume that it is zeroed out. If it is not at zero, use a flat screwdriver to adjust the almost-invisible screw head at the base of the needle so the needle is precisely on zero before testing. Also, the newer versions of the Cen-Tech load tester have upgraded the aircraft toggle to a low-profile switch just like the competing devices. Good improvement, in my opinion.

I've used this tester for over 35 years, still works! (Its a Chicago Electric and the load resistor is 50amps DC) MAKE SURE TERMINALS AND CABLE ENDS ARE CLEAN AND TIGHT! Just because it looks good that isnt enough. Connect it once and do these steps in this order. 1. Test battery standing voltage 2. Load test battery 3. Starters cranking draw (a defective starter will have a higher load simulating a weak/bad battery) 4. Alternator output Also, batteries are often "up" labeled on capacity ratings so a battery rated for 900 cca may only test at 800+ when new.

Out of the 633 of us.............I bet 80% of your subscribers OWN one of these now😳❤️❤️❤️❤️❤️

Who needs a digital $100 plus battery tester when this analog on does it all. This video explains it all quite thoroughly. Great presentation.

Thanks for sharing, just a couple othe things you didn’t mention, when your testing the alternator with the load tester and engine running turn on all excessories, bright lights, ac, wipers etc this will produce extra load to see how your alternator is sending juice to the battery

Extremely well done Jason. Wish I saw it BEFORE I shelled out $50 to Pep Boys! I think it is the same tester, BUT, Now I know how to use it. VERY helpful. Beats lugging in the battery every time to get tested.

Excellent video! I bought one from HF years ago and never needed to use it until today, then I realized I didn’t have ay instructions on how to use it, until I found your video! Thanks it works like a charm-my battery was toast.

Good video. FYI - Marine Cranking Amps are measured at 32 degrees F, Cold Cranking Amps(CCA) are measured at 0 degrees. A 1000 MCA rated battery is roughly equivalent to 800 CCA

Best! Battery Tester Video I've seen...💦..Big Thank You, to Jason

I can't believe I was unaware of these load testers. I started thinking about the need for such a thing this AM glad there is such a cheap product option out there. For a hobbyist the Cen-Tech is probably just fine!

Some people will argue that it only puts a 100 amp load. Most batteries can be well over 550 CCA. They say the tester should test half the CCA of the battery. Well, the load testers' instructions say to test for 10 seconds and let cool for 1 min. The test cycle is 3 tests in 5 min. I've been using these for years at a professional shop. Electronic testers work well but you have to know CCA and/or amps. If the stickers are gone you can't know this. The load tester doesn't need this and it is much faster. Also, an electronic load tester may say good recharge whereas a load tester will say weak. When viewed In an escalating 0 to ok scale. The bar graph on the electronic will show the amps closer to zero but will say the battery is good. Vs the load tester just tells you it's weak. If we were to only see the graph itself without the outcome most all of us would say replace the battery and that's the difference between being stranded or not. Load testers for the win IMO.

Thank you so much. You're the 1st one I've been able to learn anything from watching KZfaq. I plan to follow from here on out.

Had one of those devices for 3 years and just realized I was using it wrong. Thanks so much! I feel like a fool. I have a bad habit of not reading directions.

Thank You for this video , it was amazing, getting round to it , no excessive talking . Very instructive. I give it 2 thumbs up and a “Like”.

Absolute killer video❤️ You explained everything perfectly👍🏽 So that even “POLITICIANS” or “LAWYERS” WILL UNDERSTAND! HARBOR FREIGHT should pay you a $1 Commission for everyone that you sell! Because that’s where I’m going now❤️😡

Great tool to have.Many batteries may hold voltage but they lost amperage and there is no way to know just by voltmeter, especially AGM and sealed batteries where you can't measure the acid...I bought load tester for my solar battery bank, now I know if any of my batteries going bad, because if in series it takes only one bad battery to take down whole string...

Nice video and explanation and demonstration of a manual car battery load tester! I never knew there was a heating element inside the load tester that was used to draw the load from the car battery! Very inexpensive way to test a battery just before winter! Most car batteries will last 5~6 years at best and a car battery load test is a very inexpensive and low tech tool that everyone who owns a car should have in their DIY tool box.

This is a great video! You explained how it works, and precautions in a simple manner.

Great easy to understand video,you didnt talk about the lower (yellow) scale regarding crank voltage.

Read the instructions, what? I'm too smart for that! Cost me hours of cleaning connections, installing a new starter and massive embarrassment when the battery turned out to actually be the culprit. I had been told that, "Advance Auto Parts checked the battery and found it "Good"". I double checked that finding with my trusty Harbor Freight Load Tester, and confirmed their result more than once. Been many years since I last used it, and apparently forgot the procedure you outlined... To my detriment! I just checked that same battery again, with the same meter, and it's VERY obviously bad. Who knows, maybe I'll learn from this.

Thank you for taking the time to show an dyi how to use this device. Now that i know how to use this. I will definately be buying 1 of these.

This was exactly what I needed to know. I wanted to know if I could test a battery when it was not installed in a vehicle. This was a GREAT video and it explained everything so clearly. Even a dummy like me could follow it 😁😉

Figured I should buy one of these load testers after jump starting my MIL's car. Covid has a lot of people not running their cars as much. Thanks for the tutorial.

Great video. Living on a farm I have over 20 different pieces of equipment that take batteries. From tractors to generators to cars, trucks, motorcycles, mowers and snowblower I'm always replacing batteries in something. Don't know why I never bought a load tester but on my next trip to town I'll be stopping at Harbor Freight for one.

You can do all of this with just a cheap but accurate voltage multimeter, tripod with cellphone video recording on the meter display, and a screenshot of this battery load tester for reference; using the car starter as load and you can record the initial voltage of battery, the voltage drop when starting, and the charging voltage when car is started.

Fantastic video! I just picked one up today on sale reg $35.00 on for $14.00 🙂

Jason thank you for the awesome video. I learned what I needed to learn from you. Thank You Again for taking the time to educate us and making our time to get things done more valuable!

Your video instruction is one of the best on KZfaq, buddy! Followed you for more! Thanks for sharing

Hes very pleasant. Its easy to understand!! He addresses all imp issues!!!

Very clear description and demonstration.

Thank you I just bought one I didn’t understand how to use the seller done bad job in explaining But the video was an excellent

Good job I would add that, You need to take the readings and calculate the internal resistance of the battery. That is the parameter that really matters..

That tester really comes in handy. They had those around even when I was a kid so we're talking 60s and 70s and they were still using them in gas stations all the way up until the 90s. I used to have a electric reservoir boat in the '90s. I had testers battery chargers battery acid I also had one of the devices that you would take the caps off the battery and check the fluid and it would tell you if that cell is bad or good. For a million dollars I cannot think of the name of that gauge. I always know the name of that and right now my mind is blank. But that is absolutely the best method to find out if you have a bad cell. Even though modern batteries are all pretty much maintenance free you can still use a small enough screwdriver to take the caps off. If you find one of your cells is down you can ONLY use distilled water not a bottle of deer Park distilled water there's no minerals in distilled water. You can find it in most every drugstore and sometimes convenience stores. If you do a Google search on the gauge it will give you the name of it and they're not very expensive. Now you really don't need a big container of acid if you're only working on car or truck batteries. At any given time during any open boat season I could have anywhere from 10 to 12 batteries and some people would even have more than that. You gave a very good demonstration on how to use this device. I always like to watch when people give demonstrations sometimes you learn something that you never knew. Thanks for sharing your knowledge look forward to seeing your next video.

Thanks for the video. I recently bought one of these that's Buffalo Tools branded (probably made in the same factory, it looks exactly the same as the Cen-Tech). The manual it came with was not very good. Your video cleared up a lot of stuff on how to use it.

Thank you very much for your video, I learned a lot how to test battery and I’m already bought one of these load tester, keep making an educational videos.

Thank you for a step by step, easy to understand video.

I use this for a load test. To analyze the battery CCA and resistance I use the yellow cen-tech digital battery analyzer

Great job. I just bought this tester today and needed this video. Thanks.

Best explanation so far. Thanks

Excellent video! Clear and helpful instructions. Thank you.

Looks to me like the needle was at the beginning of the 800 range, not the 1000 range.

Thanks for info on Cen-Tech (buying today) but Just fyi....these batteries that charged over night and are still weak, need to be left on for a few more days. I just recently learned this after having discarded some batteries too early. I have 6 batteries in my barn right now going thru this multi-day charging because of our cold snap...its a long process, but may avoid wasting money.

Excellent video. Just bought one and with your help I now know how to use it. THANKS

Thanks I could have used this when I took my mom's car to the gas station as a favor and filled up the tank and then it wouldn't start. I thought it was the battery but this man at the gas station argued me up and down telling me it couldn't possibly be the battery because it's trying to crank and all my lights are working. So I paid a tow truck $90.00 to take it to a shop and then payed them another $140 for a diagnostic and of course it turned out it was just the battery.

Great video, I was looking for 2 minutes or less, but watched at a higher speed, well worth my time. :)

thanks so much for explaining things. i am refurbinshing my 1st battery and bought this today. going to come in handy after these 5 rounds of 15 minutes on the 200 amp.thanks a lot

@4:28 - the battery voltage is 12.4v ( about 66% capacity ) . While load testing, the voltage dropped down to 11v and settled at just above 800 CCA. A healthy battery even at 66% capacity should not drop that fast during this type of load test.

Thank you that was excellent info...

Thank you for the description. I have one of these and clearly missed some of the details you pointed out. This video helped me out greatly.

Scored one at Walmart clearance isle less thank HF....thanks for the vid

I don't have a buddy and I do not go to auto parts stores - oh and even if I had a buddy, chances are, he won't have a car. Get to the point which is showing a load test. sheesh - ok at the end you did a better job. Thanks - finally

It would've been good if you showed how to use this load tester to Load Test both the Charging System and the Starter. Cheers

Very Good, simple and thorough and to the point.

Amazing video way better than the owners manual

Thank you brother for another great video. I got learned a lot. Thanks again and GOD BLESS. Mike

Great video for the novice. Thank you

Great simple and clear explanation....thank you

Cool. I just bought one yesterday at Harbor Freight.

Thanks for the information. My main cranking battery on my boat reads 12.6 and it will not start the engine. I can jump it with the trolling motor batteries but there's clearly a problem. Now I can check to see if that's the problem. Great video and I subscribed!!!

You covered all the bases excellent tutorial.

Jason thank you for a good video, i bought one at harbor freight I think it will come in handy. I have a riding lawnmower, atv, and two cars. Thank you 👍

Good, simple and clear instructions. Thanks.

True, Voltage means NOTHING on a battery. The capacity is more important. Many bad batteries will show 12V but not have enough current to run the load. Just like a starter, just because you see it shoot out and spin free does NOT mean its working. When people test a starter, they test it with a zero load. The true test is a loaded starter test

great video. what you stated at the beginning of the video was exactly what happened to me. lol

Very timely and informative

Thanks for sharing this with us, and God bless you!

Very helpful

Going to get one tomorrow

Nice, informative and to the point. Keep it up. Cheers.

Thanks for a great video Jason. Surely will helps me.

CCA rating is tested at 0°F. This battery would fail CCA. If you live some where will you know the winter going to be cold, e.g. Minnesota, Wisconsin. Simply take your battery out and put it in the freezer for 12-24 hours, deep freezers will be down to single digits. Rehook it back up and see if it can start your or not. That is a better test than this tool will ever be.

Great video. I got a few batteries sitting around to test.

Thank you for posting. This was very helpful.

Thanks, you did a great job

Excellent video Mr Jason, Very didactic, even though you are not a Harbor Freight Tools salesman, I manage to motivate myself to buy one. Thank you very much for uploading the video, I am your new subscriber, Have a good day.

thanks for the very thorough well explained video on how to use this

Bought one of these on Amazon. The switch on the bottom was broken. Returned it and got a replacement. That one was also broken. ( The gauge was falling off and something rattling inside ) . I've yet to get my money back.

Very helpful, thanks. 😊

Awesome video. Real teacher!

I just bought one and it caught fire... Granted it was a return they had marked as tested

Looked like it was at the beginning of the 800 range, not the 1000

Great video. Buying one today!

I just recently purchased this load tester but both the directions and this video did not explain how to use the "LOAD VOLTS" and "MIN CRANK VOLTS" in the yellow area. Can someone explain how I would use this information? Thanks.

I just bought a Centech load tester. I've since learned the Centech load tester is useless for performing accurate load tests. The first requirement for an accurate load test is the load has to be applied for 15 seconds. The Centech user's manual says to only apply a load for 5 seconds. That's the first Centech fail. The second requirement for an accurate load test is to take the rated CCA of the battery and divide it in half, then apply that load for 15 seconds. There's no way to adjust the Centech load tester to put a load half of my battery's CCA (850 CCA). I believe though I'm not sure the Centech only applies a 100 amp load and for a maximum of 5 seconds. That makes the Centech load tester a toy that makes the user feel good about "load testing" his/her battery.

At 00:50, a 12 V battery is less than half-charged. A full charged battery is anywhere from 12.6 V for a FLA battery to about 12.8 V for an AGM. A voltage test is quite useless. It only shows the state of charge, but not the state of health of a battery.

Excellent Tutorial...Thank You.

Great video, terrible battery. The quality of these Interstate batteries has gone right off the deep end. That could be one of the reasons that this one load tested at 800...

Great explanation! Thank you.

If you are handy enough, it's a great tool, the video is very instructive and can get you out of trouble. Now, I have a question, I wonder if I'll get an answer to it: There's the harbor freight digital tester which I guess is not capable of testing "load", is it worth for any reason to have both?

Thanks so much the information was so handy and useful!!!💯💯💯😀😃

🎉 what a Great video! thank you!

Thank you for the video

Thank you for the lesson very good

You would make a good school teacher especially is shop classes if you taught in a tech HS.

Muy bien explicado. Sos un capo.

Great Video Jason

Very informative .. Ty

First time I used this tester to load test a battery I had smoke coming out of the top part

It would be good if you covered the starter test if this instrument also. Bottom scale.